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Polymethyl methacrylate optical properties

Polymethyl Methacrylate (PMMA), This material has exceptional optical clarity and resistance to outdoor exposure. It is resistant to alkalis, detergents, oils and dilute acids but is attacked by most solvents. Its peculiar property of total internal reflection is useful in advertising signs and some medical applications. [Pg.15]

Methyl methacrylate is only one of a family of monomers, including the various esters of acrylic, methacrylic, and ethacrylic acids, which are polymerized to produce the thermoplastic resins known as the acrylates. A wide variety of reactions and starting materials may be utilized for their production however, the principal commercial product is polymethyl methacrylate, sold by Du Pont and Rohm Haas under the trade names of Lucite and Plexiglas, respectively. These materials were introduced to the United States market in 1936 (44) and have received widespread acceptance due principally to their outstanding optical properties. Production in 1949 was reported as about 22,000,000 to 25,000,000 pounds and peak wartime capacity was above30,000,000 pounds. While this can account for only about 2% of the current production of propylene for chemical purposes, the acrylate resins are of considerable commercial importance as they are sold at a relatively high price and are the only materials available that will meet the requirements for certain military and civilian products. [Pg.318]

Acrylic. Acrylic resins (polymethyl methacrylate) have exceptional optical clarity and good weather resistance, strength, electrical properties, and chemical resistance. They have low water absorption characteristics. However, acrylics are attacked by strong solvents, gasoline, acetone, and similar organic fluids. [Pg.369]

The acrylic plastics use the term acryl such as polymethyl methacrylate (PMMA), polyacrylic acid, polymethacrytic acid, poly-R acrylate, poly-R methacrylate, polymethylacrylate, polyethylmethacrylate, and cyanoacrylate plastics. PMMA is the major and most important homopolymer in the series of acrylics with a sufficient high glass transition temperature to form useful products. Repeat units of the other types are used. Ethylacrylate repeat units form the major component in acrylate rubbers. PMMAs have high optical clarity, excellent weatherability, very broad color range, and hardest surface of any untreated thermoplastic. Chemical, thermal and impact properties are good to fair. Acrylics will fail in a brittle manner, independent of the temperature. They will suffer crazing when loaded at stress about halfway to the failure level. This effect is enhanced by the presence of solvents. [Pg.67]

Contact lenses are the most common polymer product in ophthalmology. The basic requirements for this type of materials are (T)excellent optical properties with a refractive index similar to cornea good wettability and oxygen permeability ( ) biologically inert, degradation resistant and not chemically reactive to the transfer area ( ) with certain mechanical strength for intensive processing and stain and precipitation prevention. The common used contact lens material includes poly-P-hydroxy ethyl methacrylate, poly-P-hydroxy ethyl methacrylate-N-vinyl pyrrolidone, poly-P-hydroxy ethyl methacrylate, Poly-P-hydroxy ethyl methacrylate - methyl amyl acrylate and polymethyl methacrylate ester-N-vinyl pyrrolidone, etc. The artificial cornea can be prepared by silicon rubber, poly methyl... [Pg.177]

Poomalai, R, Varghese, T. O., and Siddaramaiah. 2009. Ethylene methacrylate (EMA) co-polymer toughened polymethyl methacrylate blends Physico-mechanical, optical, thermal and chemical properties. Polymer-Plastics Technology and Engineering 48(9) 958-965. [Pg.172]

Bahners et al. [68] investigated the concepts of technical fibers for the special coated fibers to be used for textile solar collectors. The technical fiber made of different polymers (polymethyl methacrylate (PMMA) and polyethylene terepthalate (PET)) were characterized with respect to optical properties relevant for the model. The fibers were coated with a matrix of 5% polyvinyl acetate (PVA) in methanol, into which fluorescent dyes were dispersed. The wave guiding behaviors of the technical fiber over greater lengths were quantitatively analyzed by a logarithmic fit. The measured value was found to divert from the ideal fit at larger fiber lengths. [Pg.277]

PMMA (Acrylic, also known as Perspex) - is often used for its optical properties. Polymethyl methacrylate absorbs very little incident light, infact the light transmission through a parallel sheet free from faults is about 92%. The mar resistance of acrylic polymers is poor and is often upgraded through the use of a clear hardcoat... [Pg.194]


See other pages where Polymethyl methacrylate optical properties is mentioned: [Pg.424]    [Pg.2351]    [Pg.298]    [Pg.742]    [Pg.84]    [Pg.6]    [Pg.169]    [Pg.339]    [Pg.400]    [Pg.472]    [Pg.2351]    [Pg.301]    [Pg.819]    [Pg.481]    [Pg.509]    [Pg.261]    [Pg.619]    [Pg.807]    [Pg.424]   
See also in sourсe #XX -- [ Pg.669 ]

See also in sourсe #XX -- [ Pg.242 ]




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